Infection following a knee replacement is one of the most serious complications a patient can face. It often requires further major surgery, prolonged antibiotic treatment, and, in severe cases, removal of the implant to treat successfully. While this complication remains relatively uncommon, the consequences are significant enough that minimising the risk deserves as much attention as the surgical technique itself. As part of his ongoing research, Mr Sven Putnis co-published data following patients with periprosthetic knee infections over a 15-year period. He uses these findings to inform a rigorous, multi-stage infection-prevention protocol for every knee replacement he performs in Bristol.
Understanding the Risk of Infection
Bacteria live naturally on our skin and on every surface we touch. They cannot be entirely eliminated, only carefully managed. Careful airflow regulation and sterile draping alone are not enough to prevent infection. A detailed, disciplined protocol at every single stage of the surgical journey, from weeks before surgery through to months afterwards, is essential to keep infection risk as low as possible.
Mr Putnis's Bristol Knee Replacement Infection-Prevention Protocol
Pre-Operative Planning
- Skin swabs taken in advance to check for resistant bacteria such as MRSA.
- Diagnosis and treatment of any underlying infections elsewhere in the body before surgery proceeds.
- Identification and healing of any cuts, grazes, or skin breaks on the leg well before the operation date.
- Anti-bacterial skin wipes used in the days leading up to surgery to reduce bacterial load on the skin.
- Careful monitoring and optimisation of underlying conditions such as diabetes, which is strongly linked to infection risk.
- Anaemia identified and treated in advance, since anaemic patients are more likely to need transfusion and have poorer wound healing.
Day of Surgery
- The knee is reviewed, hair shaved from the surgical site, and washed thoroughly with a chlorhexidine and ethanol solution.
- The leg is wrapped in a sterile drape immediately afterwards, with the next exposure only occurring in theatre, right before the procedure begins.
- Surgeon and assistant wear a sterile helmet and hood system, with airflow activated only once fully gowned and sealed, a technique proven to reduce infection rates.
Intra-Operative Measures
- A single, maximum dose of broad-spectrum IV antibiotics, chosen to remain effective for the full 24 hours around surgery, is administered.
- No tourniquet is used for the majority of the procedure, reducing tissue ischaemia that can impair healing.
- An adhesive iodine-based antiseptic drape restricts exposure to the surgical approach, minimising contact with untreated skin.
- Efficient, accurate surgery minimises operative time and soft tissue trauma, as every extra minute of exposure is an opportunity for contamination.
- A heavy barbed suture creates a watertight capsular closure, sealing in any bleeding and reducing the space where bacteria could collect.
- Tranexamic acid (TXA) is used both intravenously and intra-articularly to control bleeding and reduce the need for transfusion.
- No surgical drain is required; the sealed knee joint prevents a direct route for bacterial entry from outside the body.
- Skin is closed with barbed suture and surgical glue, deliberately avoiding steri-strips, which can cause skin reactions and compromise the wound edge.
Post-Operative Care
- Post-operative anaemia is minimised through reduced intra-operative bleeding and the use of TXA, supporting faster, better-quality wound healing.
- Dressing is left intact for 12-14 days, as discharge from the wound is rare using this technique.
- Any infections elsewhere in the body (urinary, chest, dental) are fully investigated and treated early, as these can seed bacteria to the new joint via the bloodstream.
- Invasive dental treatment in the months and years after surgery is covered with high-dose broad-spectrum prophylactic antibiotics.
The Result of Rigorous Infection Prevention
This comprehensive, evidence-based approach, built from published outcomes research, has helped Mr Putnis achieve one of the lowest periprosthetic infection rates for knee replacement in the UK. This gives patients real confidence in the safety of their procedure. According to a study, infection rates for knee replacements generally range from 1% to 3%, but with a robust protocol, Mr Putnis has consistently achieved rates below 1%.
Frequently Asked Questions
How common is infection after a knee replacement?
Infection rates following knee replacement are relatively low overall, and a rigorous prevention protocol like the one described here further reduces this risk compared to standard practice.
What are the warning signs of infection after surgery?
Increasing redness, warmth, swelling, wound discharge, fever, or worsening pain after the first week or two should be reported promptly.
Why is a tourniquet not used for most of the procedure?
Avoiding prolonged tourniquet use reduces tissue ischaemia, which can impair wound healing and increase infection susceptibility.
Do I need antibiotics before dental treatment after a knee replacement?
Yes, invasive dental procedures are a recognised source of bloodstream bacteria, so high-dose antibiotic cover is recommended after joint replacement.
Why is diabetes control so important before knee replacement surgery?
Poorly controlled diabetes significantly increases infection risk, so blood sugar optimisation before surgery is crucial.
Conclusion
Minimising infection risk in knee replacement surgery is not down to a single step; it results from a disciplined, evidence-based protocol applied consistently from pre-operative planning through to months of post-operative vigilance. Mr Sven Putnis’s approach, informed by his published research on periprosthetic infection, has been developed specifically to give patients in Bristol one of the safest possible pathways through knee replacement surgery. For more details, see our Total Knee Replacement, Revision Knee Replacement, and Research & Publications pages. Considering a knee replacement in Bristol? Contact Mr Sven Putnis to discuss his infection prevention protocol, or book an appointment.
